RPM’s dropping off after steady speed

[Greg Smith]

After a sustained highway drive, if I simply kick the car out of gear and coast up an offramp, the RPMs fluctuate and drop very low until the car will die. If I run it down through the gears while going up the ramp, it’s fine. 2007GTCS, six speed trans.

 

[Noobz347]

IAC

 

[Greg Smith]

Well, I wasn’t aware the 2007 to 2009 had an IAC. . Thanks.

 

[Noobz347]

Me either, one way or the other.

 

[Noobz347]

Have you pulled codes (regardless of whether the light is on or not)?

 

[Dino Dino Bambino]

After a sustained highway drive, if I simply kick the car out of gear and coast up an offramp, the RPMs fluctuate and drop very low until the car will die. If I run it down through the gears while going up the ramp, it’s fine. 2007GTCS, six speed trans.

The inside of the throttle body between the blades and the bores may have enough dirt deposits to restrict airflow when the throttle is closed. Remove the TB and clean it thoroughly.

 

[Greg Smith]

Have you pulled codes (regardless of whether the light is on or not)?

Yes, no codes pending or active.